Multimedia messaging services will provide additional content to mobile communications, such as the transmission of audio and video clips, photographs and images, combined with the traditional text messaging.
In communications systems providing multimedia messaging services (MMS), terminals like mobile stations or personal computers (PC) will be able to send and receive multimedia information as far as they are equipped for a respective content. First MMS mobile terminals will be able to send and receive multimedia messages that include still images, text, and possibly sound, while other terminals are already able to handle video clips. A next generation of MMS mobile terminals will also be able to handle in addition multimedia messages including video clip. Thus, in particular at the beginning, there will terminals which can transmit multimedia messages including video clips, but also a great number of terminals which can handle only images. Also similarly equipped terminals may have different characteristics like for example different image resolutions or memory sizes, which equally has an effect on the services that can be made use of.
Some terminals, like PCs, may allow an upgrade of their capabilities, e.g. by plug-ins. An upgrade then enables the terminal to make use of desired multimedia messaging services.
Another possibility is that a content creator prepares several versions of the same service, to match e.g. different browsers, and thus to make a service available to differently equipped terminals.
With other terminals like mobile terminals, in contrast, the possibility of an upgrade will be rather limited. On the other hand, many contents will not be multi-version content creations, in particular those created by non professional users.
Thus it is desirable to be able to adapt multimedia content that is delivered to the capability of the receiving terminal. Such an adaptation of multimedia content can be carried out before delivery to the receiving terminal, in particular at a multimedia messaging service center of the network side of the communications system, which multimedia messaging service center also takes care of delivering the multimedia messages to the respective receiving terminal.
An example of a possible content adaptation is the modification of the resolution of a transmitted image in order to make it fit to different displays. Another example is a reduction of the message size in order to avoid transport or memory problems of the receiving terminal. Another adaptation can be given in form of a transcoding between different coding formats for the same media type, like a conversion from a JPEG image to a GIF image.
Because of the variety of MMS terminals in terms of capabilities, manufacturers etc., it will be important to provide content adaptations which are as comprehensive as possible. Content adaptation should not only be enabled for transmissions between terminals with similar media characteristics, e.g. between image phones, but also across media types, e.g. for transmissions between video phones and image phones.